We are a family of 4 with 2 boys 14 and 12 travelling to Greece this summer. As a day trip from Athens, we would like to visit Cape Sounion to see the Temple Of Poseidon. We would like to then spend a few hours at a beach after the visit. It appears that we could walk down to a small beach below the temple in Sounion. As we were thinking of taking the bus, this would be the easiest. I don't want to miss an experience just for convenience however. My questions are 2: Are the beaches at the resorts in Sounion nicer, close enough to access by foot or taxi and available to visit for a fee? And 2: Are the beaches farther up the coast (Vouliagmeni, Varkiza) worth an extra bus or taxi? My boys would prefer something on the livelier side if possible. Thanks for any help you can offer.

The sandy beach of Sounion (beds, umbrellas, showers) is unique becusse the temple just above. Only a few steps froom the bus stop.
Varkiza is a good and rather large sandy beach (beds, etc., big self service restaurant). Bus stop in front of the entry.
I prefer Varkiza to the 2 sandy beaches of Vouliagmeni which is closer to Athens, however.

We have stayed many times in Sounion. The beach there is a thin strip of grainy sand often wall to wall tourists/hotel guests on the weekends. You can walk down to the beach either from the road or the brambly (watch for the thorny bushes) footpath that runs down to the sea from the Temple.

I think you can pay a fee for entry on weekends, but depending when you get there it may be hard to find anywhere to put a towel down!

Vouliagmeni has an OK beach, wider than Sounion, but also packed on the weekends.

The more south (or closer to Cape Sounion) you are the nicer the beaches. Sandy beaches in coves, lined with rocks.

The beach just below the Cape is small but pretty.

Anavyssos Bay is very beautiful - there is one very large beach and a smaller beach at the landbridge to the small island with the church on it.